This invention concerns an electromagnetic hinged-armature relay having a contact spring with a bounce retarder attached to an armature for reducing contact bounces.
Hinged-armature relays, for example for use in motor vehicles, typically bounce from one to four times upon closing of normally-open make contacts and three to ten times upon closing of normally-closed break contacts, whereby for each bounce, depending upon a load being switched, strong arcs are sometimes ignited which cause high contact wear, which, in turn, negatively affect the life of such a relay.
European Patent EP 0 281 384 B1 discloses an electromagnetic hinged-armature relay which has a miniature air cylinder dampener as a bounce dampener which, depending upon requirements, is provided to reduce noise production of the electromagnetic relay.
Aside from the facts that such a solution is quite expensive and, because electromagnetic hinged-armature relays are manufactured in such volume, represent a large costs factor, it is also questionable if such an arrangement sufficiently protects contacts against consumption by burning.
German Patent DE 26 02 362 A1 discloses an arrangement for suppressing bounces of a closing armature of flat relays, in which, a device is provided at an area of a free end of the relay for absorbing movement energy of the armature after its impact on the relay core.
One or more additional masses can be provided on the armature of the relay to serve as such a device.
Aside from the fact that the solution suggested here is also structurally quite expensive, a transfer of this solution from a flat relay, as disclosed, to a small-structured hinged armature relay is not possible without further changes because the mounting space to attach such an additional device is generally not available, at least not without a disadvantageous enlargement of the structural volume of the hinged-armature relay.
It is therefore, an object of this invention to provide an uncomplicatedly-constructed and cost effective hinged-armature relay in which contact bounce is substantially prevented by structural measures which are particularly uncomplicated.